Hi @toptre123
Thank you for posting this in Microsoft Q&A.
I understand that you are trying to apply a license to an External Tenant app proxy on Entra.
Yes, you are correct App proxy requires Microsoft Entra ID P1 or P2 licenses and in external tenants, "Enterprise applications" is in preview.
Features or capabilities that need a premium license are currently unavailable in external tenants during preview. The external tenants do not have access to the app proxy capability.
For more information regarding supported features in external tenant: https://learn.microsoft.com/en-us/entra/external-id/customers/concept-supported-features-customers#compare-workforce-and-customer-tenant-capabilities
Hope this helps. Do let us know if you any further queries.
Thanks,
Navya.
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